1. Field of the Invention
The instant disclosure relates to a multi-band antenna, and more particularly, to a multi-band antenna for wireless communication signal receiving and transmitting.
2. Description of Related Art
Antenna is an important component of modern wireless-communication devices. The main function of an antenna is to provide signal reception and transmission. Antennas of different shapes and sizes can be found in the entire range of 3C products, including laptop computers, mobile phones, GPS (global positioning system) navigators, digital TVs and many other applications. Different communication standards often require antennas having different operating frequency bands. Moreover, as modern wireless-communication devices grow lighter and smaller, the research for wide-band miniaturized antennas receive much attention.
Multi-band antenna designs encounter a technical challenge of antenna size miniaturization because the negative effects of coupling interference between nearby antenna components may become more influential as the antenna's physical dimensions are reduced. The coupling interference between each component on a miniature multi-band antenna in close proximity may cause serious of impedance bandwidth, antenna gain and efficiency.
Conventional multi-band antennas often include a substrate, a plurality of antenna radiation portions, a grounding portion, and a feeding portion. The multi-band operations can be achieved by incorporating several compositions that support different resonant frequency bands on a single antenna unit.
However, the conventional multi-band antenna cannot fully support the Wi-Fi (2.4 GHz), Bluetooth (2.4-2.5 GHz), WiMAX (2.5 GHz), GSM900/1800 and GPS (1.57 GHz) operations. Consequently, it is difficult to concurrently integrate the operating bandwidths for wireless networks, mobile phones, and global positioning systems into a wireless-communication device having only a single antenna unit.
Based on research and related industrial experience, the inventor proposes the following solution for addressing the above issues.